The technology, which consists of making use of a porous wick to supply an area where there is a heating means for the evaporation of the active substance stored in a container, is already known, as are commercial appliances or devices for diffusing active substances by means of a cylindrical wick contained in a bottle produced by means of blown injection and wherein the cylindrical wick which protrudes to the exterior of the bottle is warmed with an electrically-operated heating element, bringing about the heating, evaporation and, therefore, the diffusion of the active substance to the environment.
Appliances and devices of this type are used for releasing not only aromatic active substances to the environment, but also for releasing active substances intended to be used as repellents or as compounds for eliminating insects, etc.
To be specific, we may mention appliances described in patents held by the same applicant, such as WO 02/28442; WO 98/58692; EP 0689766 A1 and WO 98/57674.
In all those documents the wick in contact with the active substance has a cylindrical configuration, which means that the heater also has to have a cylindrical geometry.
However, the patent now abandoned EP 0722742 A2 describes a device of the type referred to wherein the wick is flat and is associated with a heat-formed container, though with limitations as regards efficacy of evaporation and a complication in respect of the final sealing of the product, as it is done on two different surfaces, so in practice sealing is assured by the use of two heat-formed receptacles, one inside the other.